step(ci,(ci,s),tm(s,[pri(naught,[]),pri(naught,[])],pri(lst,[
  ctxm(alpha_ci_2_,umc,ip, (ip,umc2), (ip,umc2)),
  ctxm(alpha_ci_2_,umc,dom, (dom,umc2), (dom,umc2)),
  ctxm(alpha_ci_2_,u,d_4, (i,d_4), (c,d_4)),ctxm(alpha_ci_2_,u,d_5, (i,d_5), (c,d_5)),ctxm(alpha_ci_2_,u,d_6, (i,d_6), (c,d_6)),
  
  pri(pc,[ctxm(alpha_ci_2_,dot,s,i_s,c_s),ctxm(alpha_ci_2_,u,bsn,i_bsn,i_bsn),ctxm(alpha_ci_2_,ci,dom, (dom,ci), (dom,ci))]),
  ctxm(alpha_ci_2_,ci,dom, (dom,ci), (dom,ci)),
  ctxm(alpha_ci_2_,umc,dom, (dom,umc2), (dom,umc2))
]))).